Picture processing method in optical measuring apparatus
First Claim
1. A picture processing method in an optical measuring apparatus which comprises a projector for radiating a slit light on a workpiece, and an image sensing device for picturing an optical cross-sectional image drawn by said slit light radiated on the workpiece, an optical axis of said slit light and an optical axis of said image sensing device being disposed in such a positional relationship as to cross each other at an oblique angle,said method comprising the steps of:
- setting windows at predetermined positions of the optical cross-sectional image on a screen of said image sensing device; and
measuring a position of center of gravity of each optical cross-sectional image in each of said windows;
wherein an amount of displacement in an X-axis direction of said optical cross-sectional image on said screen is measured, said X-axis being defined to be such a coordinate axis of said screen as to correspond to said optical axis of said slit light;
a rate of magnification of said optical cross-sectional image in a Y-axis direction is calculated from said amount of displacement, said Y-axis being defined to be perpendicular to said X-axis; and
at lest setting positions of said windows in the Y-axis direction and sizes thereof in the y-axis direction are changed depending on said rate of magnification.
1 Assignment
0 Petitions
Accused Products
Abstract
An optical measuring apparatus for use in this method has a projector for radiating a slit light on a workpiece and an image sensing device for picturing an optically cross-sectional image drawn by the slit light radiated on the workpiece. An optical axis of the slit light and an optical axis of the image sensing device cross each other at an oblique angle. Setting windows are set at predetermined positions of the optically cross-sectional image on a screen of the image sensing device. A position of center of gravity of each optically cross-sectional image in each of the windows is measured. An amount of displacement in an X-axis direction of the optically cross-sectional image on the screen is measured. A rate of magnification of the optically cross-sectional image in a Y-axis direction is calculated from the amount of displacement. Setting positions of the windows in the Y-axis direction and sizes thereof in the Y-axis direction are changed depending on the rate of magnification.
10 Citations
5 Claims
-
1. A picture processing method in an optical measuring apparatus which comprises a projector for radiating a slit light on a workpiece, and an image sensing device for picturing an optical cross-sectional image drawn by said slit light radiated on the workpiece, an optical axis of said slit light and an optical axis of said image sensing device being disposed in such a positional relationship as to cross each other at an oblique angle,
said method comprising the steps of: -
setting windows at predetermined positions of the optical cross-sectional image on a screen of said image sensing device; and measuring a position of center of gravity of each optical cross-sectional image in each of said windows; wherein an amount of displacement in an X-axis direction of said optical cross-sectional image on said screen is measured, said X-axis being defined to be such a coordinate axis of said screen as to correspond to said optical axis of said slit light; a rate of magnification of said optical cross-sectional image in a Y-axis direction is calculated from said amount of displacement, said Y-axis being defined to be perpendicular to said X-axis; and at lest setting positions of said windows in the Y-axis direction and sizes thereof in the y-axis direction are changed depending on said rate of magnification.
-
-
2. A picture processing method in an optical measuring apparatus which comprises a projector for radiating a slit light on a workpiece, and an image sensing device for picturing an optical cross-sectional image drawn by said slit light radiated on the workpiece, an optical axis of said slit light and an optical axis of said image sensing device being disposed in such a positional relationship as to cross each other at an oblique angle,
said method comprising the steps of: -
setting predetermined windows in respective portions positioned on both Y-axis sides of the optical cross-sectional image relative to a maximum portion of said optical cross-sectional image, said maximum portion being located in an X-axis direction which is defined to be such a coordinate axis on a screen of said image sensing device as to correspond to an optical axis of said slit light, said Y-axis being defined to be perpendicular to said X-axis; and measuring a position of center of gravity of each of said optical cross-sectional image in each of said predetermined windows; wherein a position of a tip, in the X-axis direction, of said maximum portion of said optical cross-sectional image is measured; two pieces of windows which are elongated in the Y-axis direction are set at a position which is a predetermined distance backwardly away from said tip in the X-axis direction; a position of center of gravity of said optical cross-sectional image in each of said two pieces of windows is measured; a reference point which has a correlation with both of said positions of centers of gravity is obtained; said predetermined windows are respectively set in a predetermined positional relationship relative to said reference point; an amount of displacement, on said screen, of said optical cross-sectional image in the X-axis direction is measured; a rate of magnification of said optical cross-sectional image in the Y-axis direction is calculated from said amount of displacement; and at least the positional relationship in the Y-axis direction relative to said reference point and the size in the Y-axis direction of said predetermined windows are changed depending on said rate of magnification. - View Dependent Claims (3, 4, 5)
-
Specification